Rheumatoid arthritis (RA) is an autoimmune disease characterized by the presence of autoantibodies, systemic inflammation and persistent synovitis affecting primarily cartilage and bone of small and midsized joints. Various inflammatory cells, including macrophages and neutrophils infiltrate the joint. These activated cells release a plethora of inflammatory cytokines and enzymes damaging local tissues. An important inflammatory mediator in RA is Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) as it is involved in the activation of the innate arm of the immune system, which comprises macrophages, neutrophils, granulocytes, eosinophils and dendritic cells, all of which contribute to progression of RA. The absence of GM-CSF was found to reduce dramatically the severity of arthritis development in the antigen-induced mouse model. There is evidence that GM-CSF is produced in RA synovium and that levels of this cytokine can be measured in RA synovial fluid, suggesting that it plays a direct or indirect role in the pathogenesis of said disease. Further, studies have demonstrated the efficacy of systemic neutralization of GM-CSF using an anti-mouse GM-CSF monoclonal antibody in an acute and in a chronic mouse model of streptococcal cell wall-induced arthritis. Previous publications relating to other RA models have reported that also in collagen-induced arthritis, and arthritis induced by methylated bovine serum albumin, treatment with a neutralizing anti-GM-CSF monoclonal antibody (mAb) decreased disease severity, whereas GM-CSF injection into mice exacerbated the disease. Further, it has been shown that administration of GM-CSF to animals suffering from experimentally induced diseases (e.g. collagen-induced arthritis, etc.; cf. e.g. Bischof, R. J. et al. Clin Exp Immunol., 2000 February; 119(2): 361-367) or to patients afflicted with diseases, such as Felty's syndrome, may worsen disease symptoms (Hazenberg B P C, et al.; Blood, 1989; 83:876-82). Thus, the administration of pharmaceuticals comprising GM-CSF antagonists may be an effective way to substitute or complement commonly used treatment of autoimmune diseases such as RA.
Despite enhanced management of RA during the last decades, it has become clear that early diagnosis and aggressive step-up therapy resulting in reduction in disease activity is crucial in order to control disease progression and for bringing patients into a stage of low disease activity or remission. In some trials, the proportion of early RA patients that can achieve remission/low disease activity may be around 50% over one to two years but in daily clinical practice remission figures are lower and so far no drug has succeeded in curing RA which for most patients is a permanent chronic disease. Stable efficacy in long-term treatment is therefore a need in many patients on DMARDs and biologics, and there is accordingly also a need to improve safety over long-term administration of drugs. Further, in RA patients symptoms such as structural joint damage persist and do not completely resolve upon treatment. Accordingly, there is a need for new medicaments, which act in patients suffering from RA, for example moderate, moderate-to-severe or severe RA.
An additional problem in the treatment of RA patients is that conventional medicaments such as MTX or other chemical DMARDs or biologics such as TNF inhibitors are frequently not reducing sufficiently the symptoms of RA experienced by such individuals. Accordingly, there is a need for new medicaments which can be used alone or in addition to known medicaments, e.g., in combination with a standard MTX therapy, or other chemical DMARDs, e.g., for patients suffering from moderate, moderate-to-severe or severe rheumatoid arthritis.
Another problem associated with the use of biologics (biotechnologically produced active ingredients in a medicine), in particular biologics that are not species-specific, for example chimeric antibodies or mouse-derived antibodies used in humans is the triggering of an immune reaction against the active ingredient that is recognized as an non-self/foreign antigen. It is therefore necessary to provide medicaments that do not induce immune reactions (e.g. anti-drug antibodies, ADA) against biologics.
The above objectives are achieved by the compositions, the neutralizing antibodies or functional fragments thereof (also referred to as active ingredients) provided herein as well as by the methods of treatment of RA symptoms using the herein provided compositions and active ingredients.
Furthermore, the present invention relates to the treatment of pain. Pain can be caused by various different stimuli such as burns, cuts or by diseases, e.g. cancer, chronic diseases such as diverse inflammatory diseases or acute diseases, e.g. headache. The treatment of pain depends on the pain intensity. The WHO introduced the term “pain ladder” in its guideline for the use of drugs in the management of pain. Originally applied to the management of cancer pain, medical professionals use it as guidance in the treatment of different types of pain. According to the recommendations of the WHO patients not suffering from severe pain should first be treated with non-opioid drugs such as paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs) or COX-2 inhibitors. When pain persists despite treatment with the first line medicaments mild opioids such as codeine, tramadol-hydrochloride and the like may be used. Patients suffering from severe pain or agonizing pain respond generally well to treatment with opioids, such as morphine and the like at the cost of side effects, which may become intolerable.
There is an ongoing need for the development of new analgesics, e.g., analgesics that are not associated with uncontrollable side effects or with side effects making their use completely intolerable, such as severe nausea, vomiting, gastrointestinal problems, dizziness, etc. Today, the most frequently prescribed analgesics are small organic molecules. However, modern biotechnology and the understanding of biological mechanisms underlying pain and the detection of effector molecules, surface receptors, etc. involved in the development and maintenance of pain opened up the possibility of designing molecules, e.g. peptides or nucleic acids, specifically targeting such molecules. For example, it may be possible to provide small interfering RNA (siRNA) molecules that switch off genes involved in the pain transmission, e.g. genes encoding nociceptors on cell surfaces. Another alternative would be to target proteins that are directly involved in the development or conductance of pain. e.g. nociceptors or down-stream molecules expressed on the surface or inside neuronal cells (cf. e.g. Stosser et al., J Mol Med (2011) 89:321-329).
Recently, receptors for factors that were originally discovered as important for the immune system or for hemostasis have been identified on the surface of peripheral neuronal cells. WO2010/071923 discloses the development of antibodies binding rodent GM-CSF and their use in animal models of pain. Antibodies directed to primate, e.g. human, GM-CSF were not tested.
Originally described as a potent stimulus of the growth and differentiation of granulocyte and macrophage precursor cells in vitro, granulocyte-macrophage colony-stimulating factor (GM-CSF) is an approximately 23 kDa glycoprotein with a four alpha helical bundle structure that binds to a heterodimeric receptor composed of subunits belonging to the type 1 cytokine receptor family. It stimulates the maturation of, i.a., macrophages, neutrophils, granulocytes, eosinophils and antigen-presenting dendritic cells, to increase their functional capacity in combating infections. Genetic ablation experiments i.e. experiments silencing or knocking out the gene of interest—here GM-CSF—in mice indicated that GM-CSF is essential for maintaining the functional activity of some macrophage populations such as those involved in clearing surfactant in the lung and in responding to certain kinds of infection or immune responses.
GM-CSF has potent stimulatory activities in vitro on progenitor cells for neutrophils, eosinophils, macrophages, and to a lesser extent erythroid and megakaryocyte cells. Results obtained in vivo with gene knockout mice suggest that the major physiological role of GM-CSF is to maintain or stimulate the functional activity of mature macrophages and granulocytes and to stimulate antigen presentation to the immune system. It does the latter by its direct effects on dendritic cell and macrophage production, but also by increasing, expression of the class 11 major histocompatibility complex and Fc receptors on macrophages and dendritic cells.
GM-CSF stimulates the functional activities of neutrophils, eosinophils, and monocyte-macrophages. These include enhancement of chemotactic activity, increased expression of cellular adhesion molecules and increased adhesion to surfaces, and increased phagocytic activity as well as inhibition and delay of apoptosis of these cells. Neutrophils represent the first line of defense against aggressions. The programmed death of neutrophils is delayed by proinflammatory stimuli including GM-CSF to ensure a proper resolution of the inflammation in time and place. GM-CSF also stimulates the capacity of these cells to mediate antibody-dependent cell cytotoxicity and to kill microorganisms intracellularly and has a ‘priming’ effect on these cells to enhance their response to subsequent stimuli for the oxidative burst (superoxide anion production), degranulation and release of antimicrobial agents, and chemotaxis. Further, GM-CSF stimulates the release of secondary cytokines and mediators from these cells including IL-1, G-CSF, M-CSF, and leukotrienes from neutrophils, as well as IL-1, TNF, IL-6, G-CSF, M-CSF, and prostaglandins from macrophages.
It is clear from the above that GM-CSF plays a key role in activating and maintaining the cell populations necessary to ward off infection. However, in some instances activation of these cell populations may be undesirable. For example, activation of the above cell lineages when no pathogen is present leads in many instances to acute and/or chronic inflammatory conditions which, in extreme cases, may be life-threatening. Similarly, treatment with or over-expression of GM-CSF may lead to excess immune activation and this may be accompanied by pain. The role of pain in RA is discussed, e.g., in David Walsh and Daniel McWilliams, Curr Pain Headache Rep (2012) 16:509-517. In such instances, it may be desirable to neutralize the activity of GM-CSF such that the pain is reduced or eliminated.
Further, it has been shown that administration of GM-CSF to animals suffering from experimentally induced diseases (e.g. collagen-induced arthritis, etc.; cf. e.g. Bischof, R. J. et al. Clin Exp Immunol., 2000 February; 119(2): 361-367) or to patients afflicted with diseases, such as Felty's syndrome, may worsen disease symptoms (Hazenberg B P C, et al.; Blood, 1989; 83:876-82) and cause painful sensations. GM-CSF receptors are expressed on peripheral nerve cells, for example on nociceptive neurons. Accordingly, neutralization or antagonizing the activities of GM-CSF may prevent the stimulus of GM-CSF exerted on such neuronal cells. Blocking nociception is an aim in many different pathologic conditions or diseases which are very painful. Thus, the administration of pharmaceuticals comprising GM-CSF antagonists may be an effective way to substitute or complement commonly used pain treatment.
It is therefore an aim of the invention to provide neutralizing antibodies and functional fragments thereof targeting GM-CSF, analgesic compositions comprising the same, and uses thereof comprising to reduce painful sensations in subjects, e.g., human patients, particularly in human patients suffering from rheumatoid arthritis or other autoimmune or musculoskeletal disorders, cancer, neurodegenerative diseases, wounds, burns, etc.
It is another objective of the invention to provide neutralizing antibodies and functional fragments thereof targeting GM-CSF, analgesic compositions comprising the same that can be used in methods of treatment of human patients suffering from RA, which are insufficiently controllable with methotrexate (MTX) alone, with DMARDs, MTX plus other chemical DMARD(s) or one TNF inhibitor. These neutralizing antibodies and functional fragments thereof targeting GM-CSF or analgesic compositions comprising the same are conventionally used in the treatment of RA patients, but are sometimes insufficient to reduce the disease symptoms, e.g. pain, or lead to a remission of disease. Accordingly, there is a need for drugs that are effective in reducing disease activity, e.g. as can be determined using the DAS28CRP clinical assessment, thereby also reducing pain associated with the underlying disease, e.g. RA. It is one objective of the present invention to provide such neutralizing antibodies and functional fragments thereof targeting GM-CSF, analgesic compositions comprising the same.
Other objectives of the present invention are:                An improvement of the general physical function in a treated individual; and/or        Preventing or reducing fatigue in patients treated with the compositions of the invention; and/or        Preventing or reducing fatigue in patients treated with the analgesic compositions of the invention; and/or        Improving the quality of life of the patient; and/or        Improving work productivity; and/or        Improving safety and tolerability of the medicament; and/or        Improving immunogenicity (e.g. prevention or minimization of the formation of anti-drug antibodies (ADA), e.g. neutralizing antibodies, against the active ingredients of the inventive medicaments.        
An additional problem in the treatment of RA patients is that conventional medicaments such as DMARDs, e.g. anti-folate compounds such as MTX, alone or in combination with other chemical or biologic such as TNF inhibitors are not to alleviating sufficiently pain experienced by such individuals. Accordingly, there is a need for new medicaments which can be used alone or in addition to known medicaments, e.g., in combination with a standard MTX therapy or other chemical DMARDs, or an MTX therapy and the additional administration of one or more other chemical DMARDs, e.g., for patients suffering from moderate-to-severe rheumatoid arthritis.
Another problem associated with the use of biologics, in particular biologics that are not species specific, for example chimeric antibodies or mouse-derived antibodies used in humans is their potential immunogenicity. It is therefore necessary to provide medicaments that induce very rarely immune reactions (e.g. anti-drug antibodies, ADA) against biologics.
The above objectives are achieved by the neutralizing antibodies and functional fragments thereof targeting GM-CSF, analgesic compositions comprising the same (also referred to as active ingredients) provided herein as well as by the methods of treatment of pain using the herein provided analgesics and active ingredients.
It must be noted that as used herein, the singular forms “a”, “an”, and “the”, include plural references unless the context clearly indicates otherwise. Thus, for example, reference to “an antibody” includes one or more of such different antibodies and reference to “the method” includes reference to equivalent steps and methods known to those of ordinary skill in the art that could be modified or substituted for the methods described herein.
Unless otherwise indicated, the term “at least” preceding a series of elements is to be understood to refer to every element in the series. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the present invention.
Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integer or step. When used herein the term “comprising” can be substituted with the term “containing” or sometimes when used herein with the term “having” or could even be replaced by consisting of.
As used herein, the conjunctive term “and/or” between multiple recited elements is understood as encompassing both individual and combined options. For instance, where two elements are conjoined by “and/or”, a first option refers to the applicability of the first element without the second. A second option refers to the applicability of the second element without the first. A third option refers to the applicability of the first and second elements together. Any one of these options is understood to fall within the meaning, and therefore satisfy the requirement of the term “and/or” as used herein. Concurrent applicability of more than one of the options is also understood to fall within the meaning, and therefore satisfy the requirement of the term “and/or” as used herein.
Several documents are cited throughout the text of this specification. Each of the documents cited herein (including all patents, patent applications, scientific publications, manufacturer's specifications, instructions, etc.), whether supra or infra, are hereby incorporated by reference in their entirety. To the extent the material incorporated by reference contradicts or is inconsistent with this specification, the specification will supersede any such material. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.